Building for Developers - Droidcon Italy 2019

Many teams are designed so that engineers can take an abstract view of the customer and focus on implementation. But when the customers are other engineers, that entire dynamic is thrown on its head.

In this talk, Ty will walk you through the best practices of building great products for developers, from team processes to the technical delivery.

Topics covered will include: Building customer personas and product strategies, Developer Experience research and analytics, customer empathy and support structures, API Design and usability, testing, code distribution, and creating great documentation.

Transcript

1. DESIGNING FOR
   DEVELOPERS
   Ty Smith
   uber.github.io
   @tsmith
   

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2. Building for
   Developers
   Ty Smith
   uber.github.io
   @tsmith
   

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3. USER
   EXPERIENCE
   @tsmith
   

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4. USER DEVELOPER
   EXPERIENCE
   @tsmith
   

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5. Developer Experience (DX) - Overiew
   — Developer Product Research
   — Developer Usability Focuses
   — Library Quality Standards
   — Best Practices for Releases
   — Managing Communities
   @tsmith
   

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6. Product Research
   @tsmith
   

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7. Standard product workflow
   @tsmith
   

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8. Developer Tool workflow
   @tsmith
   

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9. People Need Focus
   @tsmith | https://twitter.com/marcos_placona/status/882487720597237760
   

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10. Expertise Bias
    @tsmith
    

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11. Product's role in a developer world
    @tsmith
    

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12. Finding the right job for your product
    @tsmith | https://hbr.org/2016/09/know-your-customers-jobs-to-be-done
    

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13. Finding the right job for your
    product
    @tsmith | https://hbr.org/2016/09/know-your-customers-jobs-to-be-done
    

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14. Finding the right job for your product
    Crash Reporting
    -Stability
    -Time to build features
    -Insight into instability
    @tsmith | CC-BY-2.0 - Bill Ward | https://hbr.org/2016/09/know-your-customers-jobs-to-be-done
    

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15. Developer Customers
    @tsmith
    

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16. Developer Demographics
    @tsmith | Search Engine Guide
    

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17. Developer Personas
    Name Role Company
    Frank CS Student University
    Betty Founder Seed Startup
    João Engineer New Market Series A
    Paul Product Manager Hypergrowth Series C
    Sharon Staff Engineer Public SV Company
    Hannah Consultant Enterprise Company
    @tsmith | https://wiki.mozilla.org/DeveloperExperience/Personas
    

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18. Developer Research
    — Watch them integrate
    — Dig into expectations
    — Survey
    @tsmith
    

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19. Success Objectives
    — Developer Productivity
    — Developer Happiness
    — Developer Trust
    @tsmith
    

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20. @tsmith
    

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21. Usability
    @tsmith | CC-BY-2.0 - Sherman Paggi
    

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22. Autodispose
    Automatic binding+disposal of
    RxJava 2 streams.
    @tsmith | https://github.com/uber/AutoDispose
    

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23. Easy to Integrate
    dependencies {
    implementation 'com.uber.autodispose:autodispose:x.y.z'
    }
    observable
    .doStuff()
    .as(autoDisposable(this))
    .subscribe(s -> ...)
    @tsmith | https://github.com/uber/AutoDispose
    

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24. Easy to Integrate
    dependencies {
    implementation 'com.uber.autodispose:autodispose:x.y.z'
    }
    observable
    .doStuff()
    .as(autoDisposable(this))
    .subscribe(s -> ...)
    @tsmith | https://github.com/uber/AutoDispose
    

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25. Concise
    observable
    .doStuff()
    .as(autoDisposable(this))
    .subscribe(s -> ...)
    @tsmith | https://github.com/uber/AutoDispose
    

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26. Intuitive
    //-------------------Vanilla RXJava----------------
    fun doStuff() {
    subcription = observable.doStuff().subscribe(s -> ...)
    }
    override fun onDestroy() = subscription.unsubscribe()
    //-------------------Autodispose-------------------
    observable.doStuff()
    .as(autoDisposable(this))
    .subscribe(s -> ...)
    @tsmith | https://github.com/uber/AutoDispose
    

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27. Intuitive
    //-------------------Vanilla RXJava----------------
    fun doStuff() {
    subcription = observable.doStuff().subscribe(s -> ...)
    }
    override fun onDestroy() = subscription.unsubscribe()
    //-------------------Autodispose-------------------
    observable.doStuff()
    .as(autoDisposable(this))
    .subscribe(s -> ...)
    @tsmith | https://github.com/uber/AutoDispose
    

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28. Consistency
    public interface ScopeHandler {
    @CheckReturnValue
    Function forFlowable();
    @CheckReturnValue
    Function forObservable();
    @CheckReturnValue
    Function forMaybe();
    @CheckReturnValue
    Function forSingle();
    @CheckReturnValue
    Function forCompletable();
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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29. Composition
    public interface ObservableSubscribeProxy {
    Disposable subscribe();
    Disposable subscribe(Consumer super T> onNext);
    ...
    TestObserver test();
    ...
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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30. Resilient and Defensive
    @Override public ObservableSubscribeProxy apply(final Observable upstream) {
    return new ObservableSubscribeProxy() {
    @Override public Disposable subscribe() {
    return new AutoDisposeObservable<>(upstream, scope).subscribe();
    }
    ...
    };
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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31. Flexibility
    public interface LifecycleScopeProvider {
    Observable lifecycle();
    Function correspondingEvents();
    E peekLifecycle();
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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32. Flexibility
    dependencies {
    implementation 'com.uber.autodispose:autodispose-android:x.y.z'
    implementation 'com.uber.autodispose:autodispose-android-archcomponents:x.y.z'
    implementation 'com.uber.autodispose:autodispose-kotlin:x.y.z'
    implementation 'com.uber.autodispose:autodispose-rxlifecycle:x.y.z'
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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33. Testability
    dependencies {
    implementation 'com.uber.autodispose:autodispose-android-archcomponents:x.y.z'
    testImplementation 'com.uber.autodispose:autodispose-android-archcomponents-test:x.y.z'
    }
    TestLifecycleOwner lifecycle = TestLifecycleOwner.create();
    subject.as(autoDisposable(from(lifecycle))).subscribe(o);
    lifecycle.emit(Lifecycle.Event.ON_CREATE);
    ...
    lifecycle.emit(Lifecycle.Event.ON_DESTROY);
    subject.onNext(1);
    o.assertNoMoreEvents();
    @tsmith | https://github.com/uber/AutoDispose
    

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34. Debugability
    public final class AutoDisposePlugins {
    public static void lockdown() {
    lockdown = true;
    }
    public static void setOutsideLifecycleHandler(
    @Nullable Consumer super OutsideLifecycleException> handler) {
    if (lockdown) {
    throw new IllegalStateException("Plugins can't be changed anymore");
    }
    outsideLifecycleHandler = handler;
    }
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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35. Documentation
    /**
    * Entry point for auto-disposing streams from a {@link ScopeProvider}.
    *
    * Example usage:
    *
    * Observable.just(1)
    * .as(AutoDispose.autoDisposable(scope))
    * .subscribe(...)
    *
    *
    * @param provider the target scope provider
    * @param the stream type.
    * @return an {@link AutoDisposeConverter} to transform with operators like
    * {@link Observable#as(ObservableConverter)}
    */
    public static AutoDisposeConverter autoDisposable(final ScopeProvider provider) {...}
    @tsmith | https://github.com/uber/AutoDispose
    

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36. Example Code
    @Override protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    // Using automatic disposal, this should determine that the correct time to
    // dispose is onDestroy (the opposite of onCreate).
    Observable.interval(1, TimeUnit.SECONDS)
    .doOnDispose((value) -> {
    Log.i(TAG, "Disposing subscription from onCreate()"))
    })
    .as(autoDisposable(from(this)))
    .subscribe((value) -> {
    Log.i(TAG, "Started in onCreate(), running until onDestroy(): " + num);
    });
    }
    @tsmith | https://github.com/uber/AutoDispose
    

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37. @tsmith
    

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38. Quality
    Primum non nocere
    @tsmith
    

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39. Quality
    Stability
    @tsmith
    

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40. Performance
    @tsmith
    

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41. Size
    @tsmith| source: https://www.youtube.com/watch?v=CVQ8cg_WIwY
    

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42. Data usage
    @tsmith
    

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43. Transitive Dependencies
    @tsmith
    

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44. @tsmith
    

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45. Releases
    @tsmith
    

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46. Semantic Versioning - X.Y.Z
    Decimal Use Example
    X - Major API Change Changed Public
    Method Name
    Y _ Minor Feature Added New
    Functionality
    Z - Patch Fix Fixed Crash
    @tsmith
    

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47. Changelogs
    @tsmith
    

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48. Deprecation
    — Be thoughtful about
    introducing new APIs
    — Respect semantic versioning
    — Mark methods as deprecated
    — Set expected timeline or
    version for removal
    — Incentivize updates
    @tsmith
    

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49. Deprecation
    /**
    * Extension that proxies to [Observable.as] + [AutoDispose.autoDisposable]
    */
    @Deprecated(
    level = ERROR,
    message = "Replaced with autoDisposable() to match top level APIs.",
    replaceWith = ReplaceWith("autoDisposable(scope)",
    "com.uber.autodispose.kotlin.autoDisposable")
    )
    @CheckReturnValue
    inline fun Observable.autoDisposeWith(scope: Maybe<*>): ObservableSubscribeProxy
    = this.`as`(AutoDispose.autoDisposable(scope))
    @tsmith | https://github.com/uber/AutoDispose
    

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50. Community
    @tsmith | CC-BY-4.0 - Billie Grace Ward | http://uk.droidcon.com/skillscasts/11019-open-source-and-building-communities
    

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51. Issues
    @tsmith
    

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52. Contributors
    @tsmith
    

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53. DX - Wrap up
    — Developer Product Research
    — Developer Usability Focuses
    — Library Quality Standards
    — Best practices for Releases
    — Managing Communities
    @tsmith
    

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54. BUILDING FOR
    DEVELOPERS
    Ty Smith
    uber.github.io
    @tsmith
    

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